This invention relates to lubricant injection, more particularly a lubricant injector, a method of operation thereof, a lubricant injector system embodying the injector of the invention, a method of improving the performance of existing lubricant injector systems, and an injector/connector assembly.
The invention is especially concerned with a lubricant injector for use in a single-line lubrication system, a method of operation of the injector, a single-line system embodying one or more lubricant injectors, a method of improving the performance of existing systems, and an injector/connector assembly. The term xe2x80x9cconnectorxe2x80x9d as used herein means the structure, such as a manifold or a single-outlet means for connecting a plurality of injectors or a single injector with a lubricant supply line.
The invention involves a major improvement in an extensive series of injectors, lubricant injector systems and injector/connector assemblies developed by predecessors of the assignee of this invention, Lincoln Industrial Corporation of St. Louis, Mo., going back as far as 1937, reference being made to the following U.S. patents tracing the development:
Of special note are two prior injectors sold by Lincoln Industrial Corporation (and its predecessor), namely, injectors sold under the trademarks Series SL-1 and SL-32. While these prior injectors have been quite satisfactory in many lubrication system installations, they have the characteristic of being slow to vent for recharging of the injectors for the next dispensing cycle, especially when, for example, the line for supplying the lubricant is relatively long and/or the lubricant is viscous, as during cold weather. Venting (recharging) time may be as high as five hours or more for prior injectors. Further, the SL-1, SL-32 and other prior injectors which are assembled with a supply manifold (the connector) have the characteristic of requiring disconnection of the lubricant line servicing the injectors prior to removal of an injectors or injectors from the manifold for inspection or replacement, and re-connection of the lubricant line following the assembly of the inspected or replacement injector(s) with the manifold.
Among the several objects of the invention may be noted the provision of a lubricant injector which, while requiring venting for recharging, vents substantially faster than prior injectors such as the SL-1 and SL-32 injectors, and a method of operation of the injector bringing about the faster venting; the provision of such an injector, the construction and the manufacture of which are no more involved than the construction and manufacture of prior injectors such as the SL-1 and SL-32 injectors; the provision of a centralized lubrication system which may include prior injectors such as the SL-1 and SL-32 injectors, wherein all injectors, including said prior injectors, vent substantially faster than prior systems; the provision of a method of revamping existing systems, which include slower-venting injectors such as the SL-1 and SL-32 injectors, to improve the system""s performance by substantially reducing the venting and recharging time; and the provision of an injector/connector assembly, including an injector/manifold assembly, enabling the removal of an injector from the connector or manifold for inspection or replacement without requiring disconnection of the lubricant supply lines servicing the connector/manifold or the feed lines to the point(s) of lubrication, and re-connection thereof following the assembly of the inspected or replacement injector with the connector or manifold.
In addition to the above advantages, an injector of the present invention has the beneficial affect of enabling a substantial reduction in diameter of the piping or lubricant hose lines used in a centralized lubrication system, with attendant reduction in cost, and a substantial reduction in the work load of the pump incorporated in the system, with their attendant economies, including longer pump life.
The injector of the present invention is also designed for effective sealing against leakage of lubricant from the injector at high or low pressures.
In general, a lubricant injector of the invention comprises a body having an inlet for lubricant under pressure, an outlet, a measuring chamber for receiving lubricant from the inlet, and a piston movable through a stroke in the measuring chamber for the discharge of a measured volume of lubricant from the measuring chamber and thence through the outlet. Further, it has a valve responsive to pressure conditions in the inlet for operation of the injector in cycles in each of which the injector starts in a state of repose wherein pressure of lubricant in the inlet is relieved and the measuring chamber is charged with lubricant, progresses through a state for the discharge and ends in a state for venting for the recharging of the measuring chamber involving the transmission of lubricant from the inlet to the measuring chamber.
The method of operation generally involves the operation in cycles of a lubricant injector comprising a body having an inlet for lubricant under pressure, an outlet, a measuring chamber for receiving lubricant from the inlet, a piston movable through a stroke in the measuring chamber for the discharge of a measured volume of lubricant from the measuring chamber and thence through the outlet, and a valve responsive to pressure conditions in the inlet. Each cycle starts with the injector in a state of repose wherein the pressure of lubricant in the inlet is relieved and the measuring chamber is charged with lubricant. Pressure in the inlet is increased for actuating the valve placing the injector in a state for the discharge. Each cycle ends with relieving pressure in the inlet placing the injector in a state for venting for recharge of the measuring chamber involving the transmission of lubricant from the inlet to the measuring chamber.
A lubrication system of the invention comprises a plurality of injectors each operable through a cycle upon being supplied with lubricant under pressure to deliver a volume of lubricant and upon relief of pressure to recharge, and a system for supplying the injectors with lubricant under pressure for delivery of said volume and for venting the injectors for recharging. At least one of the injectors comprises an injector of the present invention, as described above.
The method of the invention is for improving the performance of an existing lubrication system of the type comprising a plurality of injectors each operable through a cycle upon being supplied with lubricant under pressure to deliver a volume of lubricant and upon relief of pressure to recharge, and a system for supplying the injectors with lubricant under pressure for delivery of said volume and for venting the injectors for recharging. Generally, the method comprises replacing one of the injectors of the existing system with an injector of the present invention, as set forth above.
A lubricant injector/connector assembly of the invention generally comprises a connector comprising a body having an injector-engaging face, and an injector comprising an elongate body having a face engaging said face of the connector and detachably fastened thereto. The injector has an inlet constituted by a chamber in the injector body adjacent one end thereof and an inlet passage extending from said face of the injector to said inlet chamber. The injector has an outlet constituted by an outlet passage extending from within the injector body to said face of the injector intermediate the said inlet passage and the other end of the injector body. The connector body has lubricant supply passaging therein in communication at said faces with said inlet passage. The connector body further has lubricant outlet passaging therein in communication at said faces with the outlet passage of the injector.
Another aspect of the present invention involves a sealing assembly for a lubricant injector comprising a body containing a reciprocal piston for dispensing lubricant from the body, and a pin connected to the piston and extending endwise from the body through an opening in the body. The sealing assembly is located in the opening surrounding the pin for sealing against leakage of lubricant from the body along the pin. The sealing assembly comprises a low-pressure annular sealing member having an inner edge in sliding sealing contact with the pin and an outer edge in sealing contact with a surface of the body at least partially defining said opening, the low-pressure sealing member being effective for sealing at low pressures, and a high-pressure annular sealing member having an inner surface in sliding sealing contact with the pin and an outer surface in sealing contact with said surface of the body, the high-pressure sealing member being effective for sealing at pressures higher than the low-pressure sealing member.
Other objects and features will be in part apparent and in part pointed out hereinafter.